As long as there have been windshields on automobiles, trucks, airplanes and the like, there has been the problem of removing frozen water, such as frost, snow, ice, sleet, et cetera from the exterior (and sometimes the interior) surfaces of the glass or other transparent windshields and windows of vehicles in climates where freezing temperatures are common. To accomplish this purpose, various scrapers and brushes have long been employed. Also very old in the art is the concept of having electrical heating elements built into the vehicle glass in order to remove frost and the like. A further method is the application of hot air to the interior surfaces of the vehicle window or windshield to melt the frozen water deposit on the exterior surface thereof. These prior art methods of frozen water removal can be generally placed into two classes: melting and abrasion.
While the above prior art methods eventually accomplish their objectives, problems remain with each of them. Under certain conditions, ice or partially melted snow has an amazingly good adherence to vehicle windshields end is only removed by scraping with considerable effort. Electrical heaters and hot air blowers may be ineffective in removing a large deposit of frozen water within an acceptable period of time. Further, electrical heaters and blowers typically require the engine to be turned on; electrical heaters and blowers produce a drain on the battery, and electrical blowers typically require the engine to have already reached a warm operating temperature, thereby consuming gasoline. Of course, chipping away at an ice deposit with a scraper or the like subjects the user to a prolonged period of time in weather which is less than ideal. Therefore, a need continues to exist for improved methods and apparatus used in de-icing or defrosting automobile windshields and windows.